Double tube



Nay 18 1926.

J. F. MQCK DOUBLE TUBE Filed May 28. 1925 Patented May 1s, 1926.

UNITED STATES PATENT OFFICE.

JOHN F. MOCK, OF PIIILLIPSBURG, NEW dERSEY, ASSIGNOR T INGERSOLL-RAND COMPANY, JERSEY CITY, NEW JERSEY, 'A

CORPORATION or NEW JERSEY.

DOUBLE TUBE.

Application filed May 28, 1925. Serial No. 33,398.

y This invention relates to fluid actuated rock drills, but more particularly to rock drills of the hammer type which employ concentrically arranged water and air tubes i Vfor conveying water and air to the drill for cleansing the drilled hole.

One object of this invention is to produce a mixture of air and water within a rock `drill of the hammer type for cleansing the l0 drilled hole by arranging the water tube concentrically within an airtube.

Another objectis to enable concentrically arranged air and water tubes to be. secured within a rock drill in an improved and simplified manner, and a Vfurther object is to improve generally in devices for supplying cleansing iiuid through a rock drill to a drilled hole.

Other objects will be in part obvious and vin part pointed outl hereinafter.

The invention consists of the combination iof elements,- features of construction and arrangement of parts having the general mode of operation substantially-as hereinafter de- ,scribed and more particularly pointed out in the appended claims and illust-rated in the accompanying drawing, in which Figure 1 is a side view in elevation and partly in section` of a rock drill of the stoper type, and V Y Figure 2 is a sectional view in elevation of a portion ofa rock drill showng the manner in which the air and water tubes are arranged with respect to each other and alsol showing the securing means employed for holding the tubes. f

Referring to the drawing, the invention is shown embodied in a 'rock drill of the stoper type in which Va cylinder A and a 40 front headv B are held in position by the usual side bolts (not shown). A back head C forms a closure for the cylinder A and is held in operative position with respect thereto by a pin D. Disposed within the cylinder A is a reciprocatory hammer piston E. In this instance, an anvil block F is arranged in advance of the piston E for transmitting the blows of the piston to a hollow drill steel Gr inserted within the front head B. A front cylinder Washer H is interposed between the cylinder A and the front head B for centralizing said cylinder and front head and has a bore J which serves as a seat and a guide for the anvil block F. c

The feeding element of thermac-hine, in this instance, comprises a feed cylinder K. A piston rod L slidable within said cylinder 'supports at its outer end a rock engaging pointer O and at the opposite end a piston head (not shown). Interposed between the back head C and the feeding cylinder K is a. head block P, and bolts Q. arranged on opposite sides of the machine and provided with suitable nuts R secure the feeding cylinder K to said head block.

Pressure fluid is admitted into the machine through a suitable connection S secured to the back head and admission of pressure liuid to t-he cylinder is controlled by a throttle valve T having a throttle lever U for manipulating' said valve. i In mthis instance, the cylinder A and the piston E, forming the percussive element of the machine, are of the type in which constant pressure is maintained in the rearward end of the cylinder. The distribution of pressure fluid admitted through a passage V into said cylinder `is controlled by a. rearward extension lV of the piston E. Said extension lV controls the admission of pressure fluid to the rearward and front faces of the piston E through supply passages X' and Y respectively. The pressure fluid is exhausted from the cylinder A through an exhaust port Z.

Any suitable means may be provided for rotating the drill steel within the drill hole. In this instance, a rot-ation handle b is secured to the back head C and is adapted to be grasped by the operator for rotating the machine and drill steel as a unit.

In accordance with the present invention, a pair of tubes@ and (l are preferably arranged concentrically with respect to each other and extend through the machine for conveying cleansing fluid to the drill hole. The outer tube o in this instance serves to convey water admitted into the back head through. a connection e and is of sutliciently larger cross sectional area than the tube d to form a passage f between its bore and said tube (l. A restricted portion g is formedk on the tube o at its forward end. The tube d is provided with a collar 7L near its rearward end and preferably extends through the tube c to a point near the restricted portion g. In this instance, a passage y'V provides communication between the tube (l and the throttle valve U. The passage y' is so arranged with respect to the passage V leading to the cylinder A that fluid is admitted to said tube simultaneously with the admission of pressure fluid to the cylinder A. Pressure fluid for actuating the feeding element is admitted through a passage 7a and the passage 7a preferably communicates with the throttle valve at a point near the opening of the passage j so that when the throttle valve T is moved to admit pressure fluid to the cylinder A and the tube d, pressure fluid will be simultaneously admitted to the feeding element.

In order to secure the tubes c and (l within the head block P, a water tube cap 0 is arranged about the tube c and is provided with suitable screw threads to enable said cap to be screwed into the head block. In this instance, the cap 0 is provided with a bore p which is preferably of substantially the same diameter as a collar g carried by the tube c. A packing ring fr, which may be of rubber or other suitable material, is disposed within the bore 22 forwardly of the collar q of the water tube c, and is adapted to engage said collar so that when the cap o is screwed into the head block P, the tube c is forced rearwardly into the head block. In order to hold the tube (Z firmly in position, the end of the tube c abuts the collar h of the tube (Z and as the tube c is forced rearwardly, the collar z is pressed firmly against a packing s inserted into a bore 25' formed in the head block P. Leakage of fluid between the head block P and the cap o is prevented by a suitable gasket u.

In order to admit water into the tube c, a plurality of ports e are formed in the wall of said tube between its rearward end and the collar 0, The ports are so arranged that when the tube is pressed into position, they will be in direct communication with the water connection e.

In the operation of the machine, assuming that the throttle valve U is in the position shown in the drawings and that water is admitted to the tube c, the air passing through ihe tube fl will intermingle with the water at the forward end of said tube and thus augment the water pressure for carrying the cuttings from the drill hole.

This invention has been found to be efficient in operation, it is inexpensive to manu` facture and its advantages reside in the fact that the rearward ends of the tubes may be perfectly sealed against leakage of fluid to the cylinders, and owing to the flexibility of the packings which form a seat for the tubes, the. necessitiT of constant inspection on the part of the operator regarding leakage is eliminated.

I claim:

1. In a fluid actuated rock drill, the combination of a percussive cylinder with a feeding cylinder, a back head for the pereussive cylinder, a head block forming a closure for the feeding cylinder, a water tube supported at one end within the head block extending through the back head and the percussive cylinder into a drill steel, a collar near one end of said tube, an air tube supported at one end within the head block and extending through the. water tube, a collar near one end of said air tube to abut the end of tht` water tube for prevent ing movement of the air tube in one, direction, and means arranged forwardly of the collar on the water tube to cooperate with the second said collar and with the head block for securing the tubes in position.

2. In a fluid. actuated rock drill, the coiubination of a pereussivc cylinder with a feeding cylinder, a back head for the percussive cylinder, a head block forming a closure for the feeding cylinder, a water tube support-cd at one end within the head block and extending through the back head and the percussive cylinder for conveying water to a drill steel, a collar near one end of said tube. an air tube supported at one end within the head block and extending through the water tube. a collar near one end of said tube, the cellar on the air tube to abut the end of the water tube for preventing increment of the air tube in one direction, a packing about the air tube and abutting the collar on said tube, and a c: p to receive the packing and the air tube collar for holding the tubes against longitudinal movement.

3. In a fluid actuated rock drill, the combination of a percussive cylinder' with a feeding cylinder, a back head for the percussive cylinder, a head block forming a closure for the feeding cylinder, a water tube supported at one end within the head block and extending through the back head and the percussive cylinder for conveying water to a drill steel. a collar near one end of said tube, an air tube supported at one end within the head block and extending through the water tube to convey air for augmenting the pressure of the water, a collar near one end of said tube and abutting the end of the water tube for preventing movement of the air tube in one direction, a packing about the air tube and abutting the collar on said tube, a cap screwed into the head block to receive the packing and the air tube collar for holding the tubes against longitudinal movement, and :neans for prevent-ing leakage of fluid from the head block into the cylinder.

In testimony whereof I have signed this specification JOHN F. MOCK. 

